Skoda Superb Diesel Preheating Issue

Whoa, sounds familiar! I had a similar problem with my old Opel Astra. The glow plug light was acting crazy, and the engine was puffing out smoke like a chimney when I put my foot down. Turned out to be a dodgy sensor in the heating module, part of the car electronics. It's like a little gremlin messing with the system! Have you checked the wiring and connections to the preheating unit? Could be an electrical fault.

Interesting. Where exactly should I be looking for this connection? Is it easy to spot, or is it buried deep in the engine?

Yeah, it's almost certainly a connection issue, like what happened with my Astra. For me, it wasn't obvious just by looking. I'd recommend getting it checked out by someone who knows their way around car electronics. It's probably a quick fix for them, and way cheaper than replacing the entire preheating unit. It's like trying to find a needle in a haystack if you don't know what you're doing!

Just to let you know, the workshop found a faulty connection on the preheating control unit, just as you suspected. Cost me 95€ and the problem is solved. Thanks for the guidance!